Chapter 2- microbial Cell Structure And Fuction Flashcards
Different types of light microscopy
Bright field
Phase contrast
Dark Field
Fluorescent
Specimen are visualized because of differences in constrats of specimen and environment
Bright field
Magnification
Ability to make object larger
Resolution
Ability to distinguish two adjacent object as separate and disticnt
Dyes
Organic compounds that bind to specific cellular materials
Example of common stains
Methylene blue
Crystal violet
Safranin
Chromphore
Coloured portion of dye
One dye used to color specimen
Simple staining
Two type of dye:
Basic dye
Acidic dye
Positively charged chromophore. Binds to negatively charged cellular materials
Basic dye
Acidic dye
Negatively charged chromophore repelled by cell surface result to background staining or negative stain
Difference of gram positive and gram negative. What colour they appear.
Gram positive, thicker peptidoglycan
Purple
Gram negative. Thin peptidoglycan
Pink
Example of differential stain
Gram stain
Acid fast
Endospore stain
Acid fast stain and what color of stains. Primary and secondary
Detects mycolic avid in cell wall of mycobacterium
Primary stain. Pink
Other blue
Endospore stain colour primary and counterstain
Primary green
Counter pink